Transcript for Young Cancer Patient's Parents Turn to Facebook to Save Son

Now to one family's desperate plea to save their son taking their fight to social media and getting results. 7-year-old josh hardy beat cancer more than once and now a trial medication may help him fight off a deadly infection. ABC's Steve osunsami has his story. Reporter: This morning prayers answered for Amy and Todd hardy. A North Carolina drug company is changing its mind and sending the family an experimental drug that could save their son. The hardys turned to Facebook rallying troops to save josh convincing tens of thousands of Americans to lobby the drugmaker and even the white house for compassion. The one thing I want to share is thank you so much for the love and support. Reporter: 7-year-old josh hardy beat cancer and then needed a bone marrow transplant. That transplant compromised his immune system. He's now losing a battle with a virus that threatens his breathing and could ultimately end his life. None of us can fight as hard as he has. Reporter: The drug they need is called brincidofovir and fights the virus and the company that developed it gave it away long before it was ready for patients who begged and pleaded but the government assistance ran out in 2012. Since then they've been forced to spend every resource trying to get the drug fda approved which means refusing hundreds of requests each year. From the family's point of view and little josh, they need the drug and want the drug and don't want to hear about anything else. Reporter: Overnight the makers of the drug said they reached an agreement with the fda to begin a 20-patient pilot trial tomorrow with josh hardy as the first patient enrolled. The medicine is expected to reach josh within the next 48 hours. For "Good morning America," Steve osunsami, ABC news, Atlanta.

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